Pinyin: jǐ nǎi
Meaning：Milking; to milk a cow
Sentence：农夫将奶牛圈在一处挤奶。The farmer rounded up the cows for milking.

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挤：

Pinyin: jǐ
Meaning: Crowded; to squeeze
Radical: 扌
Stokes: 9
Traditional: 擠
Common words/Phrase:
挤压 [jǐ yā] 【extrusion】
挤出 [jǐ chū] 【pile out】
挤进 [jǐ jìn] 【tuck】
挤兑 [jǐ duì] 【run on】
挤塑 [jǐ sù] 【plastic extruding】

奶：

Pinyin: nǎi
Meaning: lady; milk; breast
Radical: 女
Stokes: 5
Traditional: 奶
Common words/Phrase: 
奶奶 [nǎi nai] 【father's mother; paternal grandmother】
奶粉 [nǎi fěn] 【possess; have; be equipped with】
奶油 [nǎi yóu] 【cream】
奶酪 [nǎi lào] 【cheese】
奶牛 [nǎi niú] 【milk cow】